1. Field of Disclosure
The here described technology relates generally to an organic light emitting diodes display (OLEDD), and more particularly, to an organic light emitting diodes display having a planarization film, and a manufacturing method thereof.
2. Description of Related Technology
In an organic light emitting diodes display, a pixel circuit and an organic light emitting diode (OLED) are disposed at every pixel area on a substrate, and light emitted from the plurality of organic light emitting diodes is combined to display an image. If the organic light emitting diodes display uses a polymer film as its substrate it may have a bending characteristic. In such a case it includes a flexible thin film encapsulating layer to encapsulate the organic light emitting diodes. The flexible thin film encapsulating layer is susceptible to cracking when exposed to external impacts.
During mass production fabrication, the pixel circuits, the organic light emitting diodes, and various wirings may be simultaneously formed while forming a plurality of display panels (referred to as unit cells) on a mother substrate, and then the monolithically integrated display panels are separated into individual unit cells by cutting the mother substrate. In this case, each unit cell is divided into a display area in which the pixel circuits and the organic light emitting diodes are positioned, and into a pad area in which pad electrodes are positioned.
Particularly, in one mass production method of manufacturing the organic light emitting diodes display, the process may include the steps of (1) forming the plurality of unit cells on the mother substrate, (2) forming the thin film encapsulating layer on the display area of each unit cell, (3) attaching a passivation film to an entire upper portion of the mother substrate, (4) separating the mother substrate into the individual unit cells by cutting the mother substrate, (5) removing a portion of the passivation film corresponding to the pad area; (6) performing an examination after removing the portion corresponding to the pad area in the passivation film, (7) removing the passivation film of the unit cells that are determined from the examination to be non-defective product and (8) attaching a polarization film to such non-defective product.
The aforementioned organic light emitting diodes display has a very complicated manufacturing process, and thus is difficult to mass produce with consistency and minimized defects. Further, in the process, a partial area of an inorganic layer (a barrier layer, a buffer layer, and the like) formed on the substrate may not be covered with the thin film encapsulating layer and the polarization film and thus it is exposed. When an external impact is applied to the exposed inorganic layer, cracks can easily occur, and the cracks are propagated into the display panel, thereby causing a contagious defect that can spread across the organic light emitting diodes displays of the mother substrate.
It is to be understood that this background of the technology section is intended to provide useful background for understanding the here disclosed technology and as such, the technology background section may include ideas, concepts or recognitions that were not part of what was known or appreciated by those skilled in the pertinent art prior to corresponding invention dates of subject matter disclosed herein.